Whether based on reactionary headline trades or disappointed gamers, Sony’s big announcement of the PlayStation 4 console late Wednesday gave a boost to the shares of its more troubled rival Nintendo.

The two stocks traded in opposite directions on Thursday. Sony’s SNE U.S.-listed shares were down
2.7% to $14.08 by midday, with Nintendo’s NTDOY U.S. shares up
2% to $11.79. Earlier trades on the Tokyo market followed the same pattern, with Sony JP:6758
-2.55% slipping about 1.8% by
the close of that session, and Nintendo JP:7974
+0.34% gaining about 1.3%.

What gives? Sony hosted a high-profile event in New York City on Wednesday night to introduce the PlayStation 4. But while the company spent two hours discussing the new capabilities of the console and the games that would be developed for it, the device itself was never shown, leading many to speculate as to what the company is currently keeping under wraps.

Though both are rivals in the videogame market, Sony and Nintendo also have many differences. Nintendo is mostly dependent on its console and games business, while Sony is far more diversified across the consumer electronics spectrum. And Nintendo has tended to appeal more to the family and casual gaming crowd, so the launch of a new PlayStation wouldn’t necessarily k!ll off demand for its own new Wii U console that hit the market in November.

But both are also going after a market that has been hammered by the emergence of smartphones, tablets and social gaming. Nintendo has struggled to sell the Wii U since its launch, leading the company to cut its sales forecast for the year. And while analysts say they liked what they saw from Sony on Wednesday night, many questions remain unanswered, such as what the new PS4 will cost when it finally comes out this holiday season.

It’s possible that Thursday’s trades are a mix of profit taking and hedging. Sony’s U.S.-listed shares have jumped more than 30% over the last two months in anticipation of the new console. Nintendo has lost about 30% since the launch of the Wii U in mid-November.